Advancements in low-loss silicon nitride surface grating couplers

Korček, Radovan, Fraser, William, Wilmart, Quentin, Medina Quiroz, David, Edmond, Samson, Dominguez Bucio, Thalia, Gardes, Frederic, Milanizadeh, Maziyar, Schmid, Jens H., Cheben, Pavel, Ye, Winnie N., Vivien, Laurent, Alonso-Ramos, Carlos and Benedikovic, Daniel (2025) Advancements in low-loss silicon nitride surface grating couplers. In Smart Photonic and Optoelectronic Integrated Circuits 2025. vol. PC13370, SPIE.. (doi:10.1117/12.3043525).

Abstract

Over the past decade, silicon nitride (Si3N4) has become a leading platform in integrated photonics due to its excellent passive functionalities and CMOS compatibility. Si3N4’s unique properties have driven advancements in optical communications, nonlinear optics, and quantum information sciences. Efficient interfacing between optical fibers and photonic chips remains a key challenge. This can be solved by implementing surface grating couplers, which couple light into fibers placed above the chip, enabling wafer-scale testing. However, the moderate index contrast of Si3N4 hinders their performance. We explore the latest developments in high-efficiency grating couplers on the Si3N4 platform, focusing on innovative designs like high-index material overlays and optimized grating structures to improve coupling efficiency and expand Si3N4 applications in advanced optical technologies.

This record has no associated files available for download.

Contributors

Author: Thalia Dominguez Bucio

Author: Frederic Gardes

Download statistics